Essential for the pathogenicity of Salmonella is a specialized organelle termed the type II secretion system, which delivers a number of bacterial encoded proteins (effector proteins) into the cytosol of eukaryotic cells to manipulate host cellular functions to establish a successful infection. Translocation of host cellular functions to establish a successful infection. Translocation of effector proteins through the type III secretion machinery is thought to occur via two separable mechanisms, a chaperone-dependent pathway requiring a family of cognate small molecular weight proteins termed chaperones and a chaperone- independent pathway encoded in the amino terminus of the effector protein. Significant insight has been recently gained through crystal structure analysis of the chaperone-binding domain of the Salmonella effector protein, SptP, bound to its cognate chaperone, SicP. The structure revealed a multimeric complex of two SptP molecules that although unfolded retain significant secondary structure establishing numerous intimate contacts along th surface of four SicP molecules. The availability of the structure will allow the precise probing of structure and function of type III effector-associated chaperone complex.